Factbox-What do we know about the Putin-Trump relationship?

By Mark Trevelyan

(Reuters) - Donald Trump and Vladimir Putin have agreed to meet to discuss ending the war in Ukraine. What do we know about the relationship between the U.S. and Russian presidents?

TRUMP ON PUTIN

Trump has a history of positive and admiring comments about Putin that have long prompted criticism that he is "soft on Russia". He rejects that, saying that no U.S. president was ever tougher on Moscow.

Trump has called Putin a strong and smart leader and has said he "got along great" with him during his first term in the White House. Since the start of his second term, however, Trump has criticised Putin's conduct of the "ridiculous" Ukraine war and said that the conflict is "destroying" Russia.

Putin "can’t be thrilled, he’s not doing so well," Trump told reporters on January 20, the day of his inauguration. "Russia is bigger, they have more soldiers to lose, but that’s no way to run a country.” He has threatened more sanctions and tariffs on Russia if Putin doesn't agree to end the war.

PUTIN ON TRUMP

Putin said last month he had always had "pragmatic and trusting" relations with Trump, and voiced support for the latter's false claim that he, not Joe Biden, was the real winner of the 2020 U.S. presidential election. He said he and Trump have plenty to talk about, from Ukraine to energy prices. Putin has also spoken admiringly of Trump's courage when a gunman tried to assassinate him last year, saying he behaved like a "real man".

COLLUSION PROBE, ELECTION MEDDLING AND 2018 SUMMIT

During Trump's first term, U.S. special counsel Robert Mueller spent nearly two years investigating Russian efforts to disrupt the 2016 U.S. presidential election - in which Trump defeated Hillary Clinton - and whether there had been collusion between Moscow and associates of Trump. Mueller's 2019 report concluded that Russia had meddled extensively in the election through hacking and disinformation operations, but did not establish any conspiracy or coordination with the Trump campaign. Responding to the Mueller report, Trump declared: "After three years of lies and smears and slander, the Russia hoax is finally dead."

In July 2018, at a summit with Putin in Helsinki, Trump shocked his own aides and the U.S. public when - contradicting the conclusion of his own intelligence agencies - he said he accepted the Kremlin leader’s "extremely strong and powerful" denial that Moscow had interfered in the 2016 U.S. election to sabotage Clinton's campaign.

The late Republican Senator John McCain said no previous U.S. president "has ever abased himself more abjectly before a tyrant". The following day, Trump backtracked and said he had misspoken.

DOES PUTIN HAVE COMPROMISING MATERIAL ON TRUMP?

Speculation that Putin might have some kind of hold over Trump, and be in a position to blackmail him, was fanned by the emergence in 2017 of a document known as the "Steele dossier", prepared by a business intelligence company led by a former British spy.

It suggested, among other things, that Russia might have collected lurid details of an alleged interaction with prostitutes during a 2013 visit that Trump made to Moscow. Trump said the dossier was "fake news" that was circulated by opponents to damage him.

Many of its claims were never substantiated, and Trump's lawyers have said it was "egregiously inaccurate" and contained "numerous false, phoney or made-up allegations".

At the Helsinki summit, Putin was asked directly whether Russia had any "compromising material" on Trump or his family. Putin said he had not been aware of Trump's Moscow trip and it was "utter nonsense" to suppose that Russia gathered dirt on every senior American businessman who came to Russia.

(Reporting by Mark Trevelyan; Editing by Sharon Singleton)